The MPLS WG Archive

[Barry Hass <BHass@nexabit.com>]

Eric,

Doesn't a PE router have to handle the full Internet routing
table, plus VRFs for whatever VPNs it is supporting? I think
that what some folks are suggesting is that BGP (not "the box",
but BGP specifically) is already bumping up against scaling
limits at 100,000 or so routes, and that burdening it with the
additional responsibility of managing VPNs is not such a great
idea. ("Some folks" please correct me if I'm wrong). Can you
comment on that?

By the way, I don't have enough information to have an opinion
on this. I'm just trying to steer the discussion back to what
I thought was an interesting technical question before the
insults started to fly.

> In the  NBVPN routing environment, it is  not true that 
> anyone  in the world
> needs to be  able to reach anyone else  in the world.  Each 
> VPN  has its own
> inter-connectivity  matrix,  much  smaller  than the  
> Internet  connectivity
> matrix.  Now if you add up all the VPN routes, summed over 
> all VPNs, you may
> indeed get  a much larger  number than the  number of 
> Internet  routes.  But
> there is no one box which needs  to hold them all.  Since an 
> instance of BGP
> runs in a particular box, and only  has to deal with the 
> routes that need to
> be in that box,  you don't run up against the same  box 
> scaling problems you
> run up  against in  the Internet routing  environment.  You 
> can  design your
> system to  have a given box  handle as many routes  or as few 
>  routes as you
> want.